Fuel level sending unit
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Racer
Joined: Sep 2017
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Fuel level sending unit
Hello. My question is about installing the fuel level sending unit into a 1969. Should the O ring be wet with oil or other liquid before installed to make it easier or is there no difference? Thanks in advance and take care.
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From: New Or-leens Loo-z-anna
I wouldn't use oil...the oring could Pop Out when compressed...been there,
Leave the side of the oring dry that sits against the tank opening to keep it in place and lube the side that the sending unit rotates against until it locks.
add a gallon or two of gas to the tank for a few hours or overnite to test for leaks.
Leave the side of the oring dry that sits against the tank opening to keep it in place and lube the side that the sending unit rotates against until it locks.
add a gallon or two of gas to the tank for a few hours or overnite to test for leaks.
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One of those things they always teach in mechanics school. Always oil your orings.
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There’s been some back and forth recently about fuel leaks from the o-ring seal area. I’ve noticed that some of the o-rings being supplied are thicker than others… Not sure if it is apparent in the photo, but the o-ring out of the bag is much thicker.
I use this on the o-rings… Bought it from an aircraft supply house and is claimed to be fuel resistant with high octane fuel.
Regards,
Stan Falenski
I use this on the o-rings… Bought it from an aircraft supply house and is claimed to be fuel resistant with high octane fuel.
Regards,
Stan Falenski
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From: New Or-leens Loo-z-anna
An O-ring should be approx. .015 thicker than the groove it fits in for a tight seal/
Also...if the o-ring is TOO thick you will really have to fight with it to turn the sending unit to the lock position.
Machinist digital calipers, even the harbor freight brand is accurate enough to measure close fits...the oring should be at least .015 "taller" than the groove it fits in...the digital caliper has a metal "tail" that extends for measuring this as well as the depth of blind threaded holes, etc.
Also...if the o-ring is TOO thick you will really have to fight with it to turn the sending unit to the lock position.
Machinist digital calipers, even the harbor freight brand is accurate enough to measure close fits...the oring should be at least .015 "taller" than the groove it fits in...the digital caliper has a metal "tail" that extends for measuring this as well as the depth of blind threaded holes, etc.
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From: New Or-leens Loo-z-anna
